I'll do a compare/contrast for both games.
The Cars
Forza 2 has a wide variety of production cars and some purpose built race cars.
Grid only has purpose built race cars.
Both games require that you buy your car{s} to race in the events, while Forza 2 also gives you some unlockable cars that can be used for events. Each event has a specific car requirement, though for the most part, you do have choices on which car to use for the event.
Customizing Your Cars
Both games allow you to customize your cars, but they do it in different ways.
Both have a wide variety of colors to choose from, though Forza 2 does have a lot more options.
In Forza 2, you have much more freedom to customize your cars, than you do in Grid. Forza 2 allows you to choose from a variety of logos and you can move, resize and what not.
Both also have pre cut shapes. Again, Forza 2 is better at this, as you have more freedom to place, move, resize, etc the shapes/patterns. Both allow you to color the shapes/patterns.
Grid is more rigid and limiting than Forza 2. Part of this is due to the fact that you can get sponsors by doing well in Career Mode, so they don't want your car cluttered with logos. When you add a sponsor, the game places the sponsor's logo in certain places on the car, depending on what ranking you set for the sponsor; ie Main, Secondary or Sub. The placement of each sponsor's logo is different with each car you own, so it looks very professional.
Upgrade Parts
Forza 2 offers upgrade parts which increase the performance of your cars. The parts can increase various aspects of the car; ie braking, handling, acceleration and top speed. Upgrade parts also in crease your PI or Performance Index. This can be a problem if you aren't careful, as you may increase your braking, but still have a car that is slow as hell, but now your car is in a higher class. This means that while you have good brakes, all the other cars in your new class are going to have faster cars, usually much, much faster and with better brakes.
Grid does not offer upgrade parts to increase the performance of your cars.
Racing Formats and Tracks
Both have the usual straight up racing {road courses, street courses, enduro, etc}, but Grid also gives you drifting in it's various formats and rookie level figure 8 demolition derby.
They share many of the same tracks, but as usual there are some differences. Grid has the inclusion of many Drifting tracks and the two figure 8 demolition tracks.
Track wise, Grid is much more realistic. Grid uses proper sized tracks that match the real world, while Forza 2 has tracks that are extremely narrow. Most Forza 2 tracks only have spaces wide enough to side by side racing on the front stretch, where the start/finish line is. The rest of the track is single car wide, maybe 1 and a half car wide, meaning if you want to pass, you will have to do it on the grass, which slows you down.
Forza 2 has many made up tracks, while all the tracks in Grid are real race tracks.
AI Cars
Forza 2 cars seem glued the perfect driving line and never falter, while though semi rare, Grid has cars that spin out and even bit more rare, cars that DNF.
Grid seems a lot better at collision avoidance than Forza 2.
Both games make it so you are the only one that suffers from damage to your car, while the AI are unaffected.
The only real trouble spot in Grid is in the demolition derby event. The cars are bullet proof unless it's 2 AI cars wrecking each other. If they hit you, you spin wildly out of control into the wall and likewise if you hit them. On rare occasions, you might get lucky and wreck one of them, but that's extremely rare.
Driving Views
Forza 2 only has chase mode, meaning you are viewing everything from above and behind the car.
Grid has a variety of viewing modes, including cockpit.
Damage
Damage doesn't seem to be a factor in Forza 2 as far as car performance goes.
Grid has an extremely realistic damage model and it does affect how well your car performs. Try tearing up a tire and see how hard it its to steer.
Road Side Objects and Debris
Hitting the wall, will damage your car in both games.
Running over debris on the track can seriously slow you down and do damage to your car in Grid, but not Forza 2.
Test Drive/Free Roam
Both games have this and there's nothing special or different about them. You pick a car that you have unlocked, any of the starter cars or one of your Career Mode cars and run them around one of the tracks in the game.
Arcade Mode
Again, very similar. The only difference is the tracks and racing styles {see above}.
Career Mode
This is where the everything becomes different. Though as with all racing games, there are the pure basics; ie having to advance to unlock the higher level racing series'. Your actions/standings in Arcade Mode have no effect on your level/status in Career or Multiplayer modes.
Forza 2 allows yourself and your car to advance by racing. You can keep doing the same race{s} over and over to advance yourself and your car and get money. However, this will not unlock the higher level events/race series'. By advancing yourself, you get unlockable cars and discounts for upgrades. By advancing your car, you get discounts for other cars and unlockable cars from that manufacturer and discounts from certain regional parts makers.
In order to advance to higher racing series, you need to at least place 3rd in all the events. Placing 1st - 3rd also gives you unlockable cars. The better you do, the more you get, obviously. You can also get discounts from manufactures and parts suppliers. When you finish an event, you get the money you won, plus bonus money depending on how well you did.
You can increase the amount of money and advancement points you win by making your car more rare, by putting upgrade parts on it. As you level a car {by racing it}, your car also becomes more rare and you get more money/advancement points for you and the car.
Another difference is that Forza 2 gives advancement credit to you and your car in both Career and mulitplayer mode, while Grid treats them separately. Both games do however give you cash for doing well in Multiplayer mode that can be used in Career mode.
Grid differs from F2 in that you start out with 3 rookie licenses {North America, Europe and Japan}. In order to advance, you must gain "reputation" points. Your goal is to advance through all 3 levels of the 3 regional licenses and get the Global License. You must complete all 3 Pro levels in order to get the Global License. LeMans doesn't count toward any of the regional licenses, but counts toward your overall global reputation points. If you do the bare minimum to finish the 3 regional Pro licenses, you will not have enough points to get the Global License. Doing LeMans at the end of each season helps a lot in getting your Global License, when you get that high.
Each time you do a race event, the game reduces how many reputation points you can get the next time you do that event. Basically, it takes 50% - 75% of the points you won off the possible points available for the next time you do that event. For the Rookie levels, it only takes 50% of the points away Mid level takes 66% and the Pro levels take 75% of the points away.
MultiPlayer Mode
Both games give you money for competing and doing well in multiplayer mode, that you can take into career mode and spend.
The main difference is that Forza 2 carries the points over to your Career, while Grid treats the points as separate.
Earning Money
Both games give you money for doing well in the races, obviously. Both games reduce the possible money you can win on the easier settings and increase the money you can win on the harder settings. Multiplayer money carries over to career mode so you can spend it.
Forza 2 gives you bonus money on how rare your car is, based on the game's preset rarity rating for each car, any upgrade parts you have and your car's reputation level.
Forza 2 also makes you pay for any damage to your car out of you winnings for that race.
Grid gives you bonus money based on your sponsors and if you meet their requirements; ie finish 1st, finish 1st with no damage, finish the race, finish in the top 5, finish in the top 3, etc, etc, etc. If you are really good, you can have a lot of sponsor offers to choose from, to make the most money possible. Your main sponsor pays double if you meet the requirements.
Grid gives you a bonus if your team {just you, until you hire a team mate; see below} finishes in the top 3. Of course the better you do, the bigger the team bonus will be. However, it must be noted that until you get a team mate, you will have to be extremely lucky to beat the other teams as most have 2 drivers raking in the points for their team vs you alone for your team. You will also get a share of your team mate's winnings {again, see below}.
Team Mates
Forza 2 doesn't have this option.
Grid allows you to hire a team mate, once you have advanced enough {completed one of the 3 rookie levels}. Depending on the perspective team mate, depends on what he wants in his contract. You can get one that doesn't require a signing bonus, but wants 80% of his winnings and the team's winning {your winnings are your own}. Each perspective team mate has a pie chart and his contract requirements in the Team Mate section. They each have their own specialty form of racing as well. Just because they want a lot of money, doesn't mean they are any good. One rookie wants $7 mil signing bonus and 60% of his and the team winnings, but he sucks big time, as you can see from the pie chart and read on various forums. There are 2 extremely good team mates that you can get and won't cost you an arm and a leg, that will fill your coffers nicely, but I won't spoil the fun and name them. Just make sure you look at all the options before you sign on a team mate.
If you decide to fire a team mate, you just go into the Team Mate section under My Team and do it. Now if for whatever reason you decide you want a previously fired team mate back, don't be surprised if his voice is different. The game randomly chooses one of the "national voices" for him.
It should be noted that once you hire your first team mate, you must always have a team mate from then on. If you try to fire your team mate, but don't hire a new one to replace him, the game will just give you the old one back. So if you don't want a team mate, don't hire one in the first place. Be warned that the game will keep nagging you to do it.
An issue you will see on many forums is "wah, my team mate won't let me win, wah". Shut the fuck up and fire him, then get one that sucks if it bothers you that damned much. Ya fuckin' wuss!!!!
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